Reclosable rectangular cardboard box

ABSTRACT

A reclosable rectangular cardboard box is provided with a cover which is swingable about a folding line on the upper edge of the rear wall and has on its front edge a downwardly extending strip overlapping the outer upper margin of the front wall when the cover is closed. Slot-shaped recesses are provided at the ends of the folding line between the cover and said strip for yieldably receiving locking projections formed on the front ends of horizontally disposed flaps which extend from said side walls into the box.

United States Patent 1191 Egli v 1111" 3,794,238 14 1 Feb. 26,1974

1 1 RECLOSABLE RECTANGULAR CARDBOARD BOX [75] Inventor: Alwin Egli, Beringen, Switzerland [73] Assignee: Schweizerische lndustrie-Gesellschaft, Neuhausen am Rheinfall, Switzerland [22] Filed: Feb. 28', 1972 [21] Appl. No.: 229,854

[30] I Foreign Application Priority Data Mar. 1, 1971 Switzerland 2950/71 [52] US. Cl. 229/44 CB, 229/45, 229/51 WB [51] Int. Cl B65d 5/66 [58] Field of Search ..'.229/39 R, 44 R, 44 CB, r, 22, 4

[56] References Cited UNITED STATES PATENTS 2,116,652 5/1938 Adler .1. 229/39 R 3,438,564 4 1969 Moreton... 229/44 CB 3,404,829 10/1968 Stone 229/45 1 1 963 3,144,195 8/1964 2,543,084 2 1951 2,950,044 8 1960 3,015,430 1/1962 3,365,134 l/l968 Oberreich 229 45 Primary Examiner-Will iam T. Dixson, Jr. Assistant Examiner-Stephen Marcus Attorney, Agent, or Firm-Hill, Sherman, Meroni,

' Gross & Simpson [5 7] ABSTRACT A reclosable rectangularcardboard box is provided with a cover which is swingable abouta folding line on the upper edge of the rear wall and has on its front edge a downwardly extending strip overlapping the outer upper margin of the front wall when the cover is closed. Slot-shaped recesses are provided at the ends of the folding line between the cover and said strip for yieldably receiving locking projections formed on the front ends of horizontally disposed flaps which extend from said side walls into the box.

1 Claim, 3 Drawing Figures The invention relates to a reclosable rectangular cardboard box with a cover which is swingable about a folding line on the upper edge of the rear wall and having its two oppositely disposed side walls provided at their upper edges with horizontally inwardly folded cover flaps which in the closed condition of the cover engage the inner face of the cover.

An object of the invention is a very simple cardboard box the cover of which can be closed and locked in closed position in a very simple manner. In accordance with the invention the cover of the box has at its forward edge a downwardly folded strip which in the closed position of the cover overlaps the upper margin of the front wall of the box and has two slot-like recesses for receivingtwo yieldable locking projections provided on the forward ends of the inwardly extending cover flaps when the cover is closed. After opening the cover it can be closed again by slightly moving the cover manually toward closing position which will cause the locking projections to snap into said recesses and lock the cover in its closed position.

The drawing illustrates by way of example one embodiment of the cardboard box in accordance with the invention. In the drawing:

FIG. 1 is a view of the outer face of a cardboard blank from which can be made a rectangular box with a swingable cover attached thereto:

FIG. 2 illustrates in a perspective view the upper portion of the box with the cover in open position; and

FIG. 3 is a view similar to FIG. 2, except that the cover is shown in its closed position.

Referring to FIG l, the cardboard blank has a portion denoting the rear wall 1 of the box which, by folding lines 2 and 3, hangs together with two oppositely arranged side walls 4 and 5,'respectively. The side walls 4 and 5 hang together by folding lines 6 and 7 with a front wall 8 and a connecting strip 9, respectively; the latter being provided with an adhesive marginal portion 10 shown by hatched lines adapted to be glued to the free side margin of the front wall 8 when the blank is folded to form the box. The walls 1, 4, 5 and 8 hang together by folding lines 11, 12,. 13 and 14, respectively. with rectangular bottom wall flaps l5, l6, l7 and 18, the hatched portions of which are covered with an adhesive, and serve to form the bottom of the box when folded about the respective folding lines, whereby the flap 15 is the last one folded and forms the outermost layer of the bottom of the box.

The rear wall 1 hangs together at its upper edge by a folding line 19 with a rectangular cover part. 20, the dimensions of which are a few thicknesses of the cardboard larger than the open cross section of the covered box. The cover part 20 hangs together with two lateral strips 23 and 24 by folding lines 21 and 22, respectively, and by a folding line 25 hangs together with a front strip 26. The lateral strips 23 and 24 and the front strip 26, when folded downwardly, overlap the outside of the upper portions of the side walls 4 and 5 and the front wall 8, respectively, when the cover 31 is closed. The front strip 26 hangs together laterally by folding lines 27 and 28 with substantially triangular connecting flaps 29 and 30, the outer faces of which' are provided with an adhesive as indicated by the hatched lines. The connecting flaps 29 and 30, when the blank is folded,

. slightly greater than the thickness of the cardboard 2 are folded rearwardly and are glued to the inner face of the rearwardly folded lateral strips 23 and 24 respectively, so that the cover 31 is formed. Between these lateral strips 23 and 24 and the connecting flaps 29 and 30 are formed slots 32 and 33 the width of which is blank and which extend to both sides of the folding line 25 in the extension thereof; whereby parts 32' and 33 of these slots 32 and 33 are also disposed between the cover part 20 and the end parts of the front strip 26. These slot parts 32 and 33' form recesses or apertures in the completed cover 31 into which projections 34 and 35 of the lateral or forwardly extending flaps 36 and 37 may yieldably enter in the form of snap locking members. These projections 34 and 35 hang together with the side walls 4 and 5 by folding lines 38 and 39 respectively.

' The lateral flaps 36 and 37 are trapezoidally shaped and in the cardboard blank are separated by cuts 40 and 41 at an angle of 45 from the adjacent folding lines; the respective boundary lines of the parts 23, 24, 36 and 37 are also designated by 40 and 41 in FIG. 2, as far as they are visible, and also in FIG. 3.

The lateral flaps 36 and 37 on the side .walls 4 and 5 are provided on their upper faces (FIG. 2) with adhesive spots 42 and 43, respectively, so that the cover 31 when closed for the firsttime after the box has been filled with the desired substance will be securely glued to these lateral flaps 36 and 37. In order to open the cover 31 for the first time and to swing it upwardly about the folding'line 19 which functions as a hinge, a non-negligible force has to be applied to tear or break the adhesive connections produced by these adhesive spots 42 and 43. However, whenopening the cover 7 again after it has been closed again only a very minor force is required, and one can readily feel whether the boxhas been previously opened or not. Obviously, one may provide the closed box with a special sealing strip 44 covering a part of the cover 31 and a part of the front wall 1 which has to be torn when the box is opened for the first time.

For closing the open cover 31, it is merely pivotally moved downwardly, and this requires only a very slight pressure, just sufficient to permit the'locking'projections 34 and 35 on the box to snap yieldably into the recesses 32' and 33' in the cover 31. The flaps 36 and 37 and the folding lines 38 and 39 provide the necessary elastic yieldability. It is obvious that this closure operation of the cover of the invention is much more convenient than a known closure operation in which a cover part hanging together with the cover by a folding line has to be inserted from above. behind the upper edge of the front wall of the box. f

It is obvious that the box may be provided with an inner bag or liner made for instance, of paper or a plas tic, when there exists a possibilitythat, for instance, a

I powderlike substance with which the box is filled may escape through the slot-like recesses 32' and 33. If the box alone is not sufficient, one may employ in place of an inner bag a rectangular cover foil between the contents in the box and the lateral flaps 36 and 37 to prevent the escape of the contents of the box from the closed box. 7

What I claim is: 1

1. In a 'reclosable rectangular cardboard box having a front wall, a rear wall, a cover swingable about a folding line on the upper edge of the rear wall and two oprecess at each of the ends of the folding line between the cover and said strip, a pair of locking projections formed on the respective ones of the forward ends of the inwardly extending cover flaps on said side walls to yieldably enter the respective slot shaped recesses, and

a pair of downwardly extending side strips at respective ends of the cover for overlapping the upper margins of the sidewalls in the closed position of the cover, each of said slot-shaped recesses including-portions of slots which extend along the folding line formed between the cover and said side strips. 

1. In a reclosable rectangular cardboard box having a front wall, a rear wall, a cover swingable about a folding line on the upper edge of the rear wall and two oppositely disposed side walls having respective horizontally inwardly extending cover flaps which in the closed position of the box engage the inner face of the cover, wherein the improvement comprises a downwardly extending strip at the front edge of the cover which in the closed position of the box overlaps the upper margin of the front wall of the box, said strip having a slot shaped recess at each of the ends of the folding line between the cover and said strip, a pair of locking projections formed on the respective ones of the forward ends of the inwardly extending cover flaps on said side walls to yieldably enter the respective slot shaped recesses, and a pair of downwardly extending side strips at respective ends of the cover for overlapping the upper margins of the sidewalls in the closed position of the cover, each of said slot-shaped recesses including portions of slots which extend along the folding line formed between the cover and said side strips. 